The present invention relates to a mounting for a pump which facilitates connecting and disconnecting the pump inlet and discharge ports with respective flow inlet and discharge conduits and particularly relates, for example, to a pump mounting for use in a filtration tank forming part of an industrial filtration system for filtering and returning clean coolant to machine tools. The disclosure of U.S. patent application Ser. No. 144,058, filed Jan. 15, 1988, is incorporated herein by reference.
In industrial machining operations, such as metal cutting or grinding, a liquid is typically provided machine tools for purposes of cooling, lubricating, improving cutting qualities and preventing rust. The coolant is usually circulated to individual workstations, e.g., machine tools, grinders, etc., where the coolant additionally serves to flush the machining waste from the workstation for flow to a filtration apparatus, typically a filtration tank common to all of the workstations. One or more filters are conventionally employed in the filtration tank to separate the waste and other contaminants from the coolant. Many different types of filters and arrangements may be used for this purpose and one well-known commercially successful system is manufactured and sold by the assignee hereof, Henry Filters, Inc. of Bowling Green, Ohio. In that system, one or more horizontally disposed filter drums are located in a dirty coolant compartment adjacent the bottom of the tank. A suction is provided to the interior of the filter drums to pull coolant through the filter elements. Filter cake forms on the filter elements and drops or is removed from the filter drums for deposit on the bottom of the tank, where it is removed, for example, by a dragout conveyor.
In that filtration system, there is also provided a clean coolant tank for receiving the clean coolant filtrate. Various types of pumps may be employed to provide the suction to the filter drum and pump the clean filtrate through a header below the level of coolant in the clean coolant compartment back to the machine tools. For example, vertical turbine-type pumps have been employed. However, these types of pumps are bulky, unwieldy and are difficult to install in and remove from the tank because they require disconnection of the mechanical piping connections, such as by unbolting, between the pump and the flow inlet and discharge conduits, as well as disconnection of the electrical connections. Additionally, sufficient headroom above the filtration tank must be provided to accommodate the large vertical extent of that type of pump.
To overcome those, as well as other problems associated with the pumps and their mounting, particularly in industrial filtration systems using a filtration tank, and in accordance with the above-identified patent application, there are provided pumps which may be readily and easily removed from and reinstalled in the filtration tank without necessitating draining the tank, disconnecting or reconnecting pipe couplings, joints and electrical connections or manually closing valves and without the need for substantial headroom and overhead access space. The pumps, as discussed in that application, each have an axial inlet or suction port at its lower end adjacent the pump impeller stage and a pump discharge port which extends generally radially of the pump. As disclosed in the above-identified patent application, one pump embodiment comprises a submersible pump which may be lowered into the tank below the coolant level. The pump inlet port is connected with the suction conduit to the filter simply by lowering the pump onto a suction conduit outlet located in a false bottom in the clean coolant compartment of the filtration tank. The connection between the radial discharge port of the pump and the discharge conduit is provided in various ways as set forth in that application. For example, when the pump is lowered into the tank, the pump discharge head may be disposed in a tank receptor ring mounting a fixed discharge conduit such that coolant flows from the pump inlet port through the discharge head into the discharge conduit of the receptor ring for flow out of the tank to the machine tools.
In another form of the pump disclosed in that prior application, the discharge port of the pump comprises a discharge conduit which projects substantially radially from one side of the pump. To connect the radial discharge conduit of the pump to the discharge conduit of the tank, there is provided, as described in that application, a flexible coupling comprising essentially an expansion joint movable under positive control by pneumatic, hydraulic or mechanical means to effect connection and disconnection between the radial discharge conduit of the pump and the discharge conduit of the tank.
However, in certain installations, an arcuate or elbow-type radial discharge conduit from the pump is provided for connection and disconnection with the fixed discharge conduit of the tank. Consequently, it has been found necessary to provide apparatus and methods for connecting and disconnecting pumps of this type while retaining the benefits and advantages of the pump mounting systems disclosed in the prior application, including the capacity to remove and reinstall the pump by simply raising and lowering the pump, respectively, relative to the tank, without manual connection or disconnection of piping and with minimum headroom.
To accomplish this, and in accordance with the present invention, there is provided a mounting system for a pump of the type having a radially projecting discharge conduit, preferably for use with industrial filtration systems as previously described, which facilitates ready and easy removal and reinstallation of the pump into and out of a coolant filtration tank without draining the tank, manually disconnecting or reconnecting the pipe couplings, joints and electrical connections or manually closing valves and without the need for substantial headroom or overhead access space. For example, in existing installations, there is conventionally provided a header adjacent the bottom of the tank. The header is connected to an outlet conduit for flowing clean coolant from the tank to the machine tools. Such headers have a pipe or conduit adjacent the bottom of the tank for connection to the discharge port of each pump. In new installations, it is oftentimes desirable to provide similar-type pipe or conduit couplings in a similar configuration. Consequently, it has been necessary to develop a mounting system for submersible-type pumps of the type having a radial discharge conduit terminating in a flanged coupling wherein the coupling of the pump may be connected and disconnected to the coupling of the discharge conduit, while at the same time permitting removal and reinstallation of the pump.
More particularly, the pump, preferably a submersible-type pump, is mounted in a frame having a pair of laterally projecting guide pins on each side of the frame for engagement in vertically extending laterally spaced tracks, e.g., channels, disposed within the tank. By disposing the pins in the tracks, the submersible pump can be raised and lowered relative to the tank while maintaining the orientation of the pump about its vertical axis. The submersible pump is of the type having a lower axial inlet port and a radial discharge conduit projecting from the pump as discussed above. Supports are provided at a predetermined elevation along the tracks for engaging the lowermost pair of pins to support the submersible pump adjacent the bottom of the tank. At that support position, the axial inlet port of the pump lies in communication with the suction outlet of the filter drum through an opening in the false bottom in the clean coolant compartment of the filtration tank. However, the radial discharge conduit of the pump is spaced from the discharge conduit of the tank. To connect the pump's radial discharge conduit with the discharge conduit of the tank, the submersible pump is rotated about its vertical axis to locate its radial discharge port into sealing engagement with the discharge conduit. An O-ring-type seal is carried by at least one of the flanges connecting the radial discharge port and the discharge conduit.
To enable rotation of the pump, the tracks have cutouts along opposite sides adjacent each pin such that the pins may be vertically misaligned relative to the tracks and to one side thereof upon rotation of the pump about its vertical axis. To positively rotate the submersible pump about its axis and connect the pump discharge port and the tank discharge conduit, a plate or lever is pivoted to the tank and carries a bearing surface, for example, a roller for engaging a part on the pump. Preferably, the pump part engaged by the roller is a flanged coupling forming part of the pipe elbow of the pump's radial discharge conduit. The flange is spaced substantially from the axis of the pump to maximize the leverage when rotating the pump. The plate is pivoted by an elongated rod pivotally mounted at its lower end to the plate and at its upper end above the tank for movement between overcenter positions relative to a handle. Consequently, when the rod is displaced upwardly, the bearing surface engages the pump flange to rotate the pump about its vertical axis to engage and seal the flanged couplings of the radial discharge port and the discharge conduit. The overcenter position of the handle on the rod locks the two flanges one to the other in sealing engagement.
To disconnect the pump, the handle is moved overcenter to pivot the plate in a direction removing the roller from engagement with the pump flange, thereby enabling the pump for pivotal movement about its vertical axis. To move the pump about its vertical axis, the cutouts in the track are formed by upwardly and laterally outwardly inclined cam surfaces. Thus, when the pump is raised, the cam surfaces guide the pins into vertical alignment within the tracks, thus rotating the pump in a direction disconnecting the radial discharge port of the pump from the tank discharge conduit. Once the pins lie in vertical registry in the tracks, the pump may be removed from the tank. Also, by raising the pump, the pump inlet port is disconnected from the suction conduit outlet in the false bottom of the tank.
In a preferred embodiment in accordance with the present invention, there is provided apparatus for mounting a pump in a liquid filtration tank comprising a tank for containing liquid and having an outlet conduit. A filter is provided in the tank and a suction conduit communicates with the filter and applies a suction to the filter. A pump is also provided having an inlet port and a discharge port together with means mounting the pump for movement between an inoperative position removed from the tank and an operative position in the tank with the suction conduit and the pump inlet port connected one to the other and the pump discharge port and the outlet conduit connected one to the other for pumping liquid filtrate from the filter into the outlet conduit. The mounting means include means carried by the tank and the pump cooperable to guide the pump for movement in the tank in two discrete directions to connect the pump discharge port and the outlet conduit one to the other in response to movement of the pump into the operative position.
In a further preferred embodiment in accordance with the present invention, there is provided apparatus for mounting a pump in a liquid filtration tank comprising a tank for containing liquid and having an outlet conduit. A filter is provided in the tank and a suction conduit communicates with the filter for applying a suction to the filter. There is also provided a pump and means mounting the pump for movement between an operative position in the tank for pumping liquid filtrate from the filter through the suction conduit and into the outlet conduit and an inoperative position removed from the tank. The mounting means include means carried by the tank and the pump cooperable to guide the pump for rotational movement in the tank toward its operative position and also includes means for positively rotating the pump in the tank toward the operative position.
In a still further preferred embodiment in accordance with the present invention, there is provided apparatus for mounting a pump in a liquid filtration tank comprising a tank for containing liquid and having an outlet conduit and a filter in the tank and a suction conduit in communication with the filter for applying a suction to the filter. The pump has an outlet for connection to the outlet conduit. Means are provided for mounting the pump for movement between an operative position in the tank for pumping liquid filtrate from the filter through the suction conduit and into the outlet conduit and an inoperative position removed from the tank. The mounting means include means carried by the tank and the pump cooperable to guide the pump for rotational movement in the tank in response to movement of the pump from its operative position toward its inoperative position thereby to disconnect the pump outlet and the outlet conduit.
Accordingly, it is a primary object of the present invention to provide novel and improved apparatus and methods for installing a pump in a tank and removing the pump from the tank, the pump being of the type having a radial discharge conduit.